feat: Add a model config option to disable system prompts

[Mounayer]

Description

Closes #1432

Some models don't support system prompts, therefore, a new modelConfig option has been added: systemRoleSupported

By default, the systemRoleSupported option is true, where everything behaves as is. However, if the systemRoleSupported option is set to false, all role: "system" messages are filtered out. And the very first role: "system" message encountered, will have its content preprended to the very first user message.

Brief example, let's assume the following is our messages array, before processing:

[
    { "content": "Welcome to our service!", "role": "system" },
    { "content": "Hi, how can I help you today?", "role": "system" },
    { "content": "I need help with my account.", "role": "user" },
    { "content": "Certainly! What issue are you experiencing?", "role": "system" },
    { "content": "I forgot my password.", "role": "user" },
    { "content": "Please reset your password using the 'Forgot Password' link.", "role": "system" },
    { "content": "Thank you!", "role": "user" }
]

After we apply the filtering, and preprending the first system message's content into the first user message, we get:

[
    { "content": "Welcome to our service!\nI need help with my account.", "role": "user" },
    { "content": "I forgot my password.", "role": "user" },
    { "content": "Thank you!", "role": "user" }
]

This keeps the existing functionality untouched, while giving the option of using a wider range of models, even those that do not support system role messages!

Please let me know any thoughts or suggestions that may arise!

[nsarrazin]

Thanks for the contribution! i think this is very much needed for some kind of models like gemma & the o1 models.

I think the name of the argument is maybe a bit confusing sorry I know I'm the one who wrote it in the initial issue 😬

I think people might assume it's a field to set a system prompt. What do you think of m.systemRoleSupported instead ?

[Mounayer]

Thanks for the contribution! i think this is very much needed for some kind of models like gemma & the o1 models.

I think the name of the argument is maybe a bit confusing sorry I know I'm the one who wrote it in the initial issue 😬

I think people might assume it's a field to set a system prompt. What do you think of m.systemRoleSupported instead ?

Super happy to contribute!

Honestly, I agree. It can be a little confusing, I've updated the config option name to be systemRoleSupported instead. I think now it's more intuitive as to what it does!

[nsarrazin]

Thanks for the contribution!